Low Nitrogen Stress on Growth and Physiology of Cunninghamia lanceolata Seedlings

In October of 2013, stem cuttings of four Cunninghamia lanceolata clones FK, S 39, S 3 and Xin 6 were harvested from Kaihua Forest Farm of Zhejiang province and were cultivated by aeroponic. Experiments were carried out on low nitrogen stress (LN) on growth and physiology of seedlings during the next May to September. The results showed that LN could inhibit the growth of seedlings, promote the growth of root system, decrease leaf length breadth ratio, and increase the root/shoot ratio. The content of MDA increased, chlorophyll a and b decreased in treated seedlings. The content of soluble protein, the activity of SOD and POD increased in seedlings treated by LN.